Low ambient temperature refrigerator

• US 7,191,827 B2
• Filed: 12/23/2003
• Issued: 03/20/2007
• Est. Priority Date: 12/30/2002
• Status: Active Grant

• Current Assignee: Whirlpool Corporation
• Original Assignee: Whirlpool Corporation
• Inventors: Steinkuhl, Allan R., Stura, Marco, Tate, Ralph Jr., Wisnoski, John R., Junge, Brent A.
• Primary Examiner(s): Ford; John K.
• Application Number:
  US10/744,556
• Publication Number:
  US 20040134220A1
• Time in Patent Office: 1,183 Days
• Field of Search: 165/263, 165/264, 165/290, 165/291, 624/40, 624/41
• US Class Current: 165/263
• CPC Class Codes: F25D 23/061 with conduit means
• CPC Class Codes: F25D 2400/34 Temperature balancing devices
• CPC Class Codes: F25D 2700/14 Sensors measuring the temperature outside the refrigerator or freezer
• CPC Class Codes: F25D 29/00 Arrangement or mounting of control or safety devices
• CPC Class Codes: G05D 23/1931 to control the temperature of one space

Abstract

A refrigerator adapted for use in low ambient temperature conditions such as in an unheated garage or outdoors on a deck or patio. The refrigerator is provided with a low ambient heater to add heat to the refrigerated space when ambient temperatures outside the refrigerator are low enough that items stored in the refrigerator could freeze. The low ambient heater is controlled by an ambient thermostat located to sense temperatures outside the refrigerator. The low ambient heater and ambient thermostat are connected in the refrigerator control so that the ambient heater can not be energized when the cooling system is operating.

Claims

1. A refrigerator adapted for use in low ambient temperature conditions comprising:

a cabinet having an access opening;

a liner positioned in the cabinet having an inside surface defining a refrigerated space;

insulation between the liner and the cabinet;

a hinged insulated closure mounted to close the access opening of the cabinet in a closed position and to permit access to the inside of the refrigerator in an open position;

a cooling system for cooling the inside of the refrigerator including a cooling thermostat for sensing the temperature in the refrigerated space to energize the cooling system when the temperature inside the refrigerator rises above a selected temperature;

an ambient heater for heating the refrigerated space;

an ambient thermostat connected in an electrical circuit with the ambient heater and positioned to sense air temperature outside the refrigerator, wherein the ambient thermostat is connected to energize the ambient heater when the temperature outside the refrigerator is below a first predetermined temperature; and

further including a heater thermostat positioned inside the refrigerator and connected in a circuit with the ambient thermostat and the ambient heater, and wherein the ambient thermostat is arranged to connect the ambient heater and heater thermostat to a power supply when the temperature outside the refrigerator falls below the first predetermined temperature, and connects the cooling thermostat to the power supply when the temperature outside the refrigerator rises above a second predetermined temperature, whereby the ambient heater is energized through the heater thermostat when temperatures outside the refrigerator fall below the first predetermined temperature and the cooling system is energized through the cooling thermostat when temperatures outside the refrigerator rise above the second predetermined temperature.

2. The refrigerator of claim 1 wherein the heater thermostat opens to de-energize the ambient heater when temperatures inside the refrigerator rise above a predetermined refrigerated space temperature.

3. The refrigerator of claim 1 wherein the cooling system includes a compressor, an evaporator and a condenser connected in a cooling circuit, and the ambient thermostat is a bi-metal thermostat and is mounted to a discharge tube leading from the compressor to the condenser.

4. The refrigerator of claim 1 wherein the liner includes a pair of sidewalls and the ambient heater is mounted to at least one sidewall of the liner.

5. The refrigerator of claim 4 wherein the ambient heater comprises a pair of heater elements with one heater element attached to each of the sidewalls.

6. The refrigerator of claim 5 wherein the ambient heater elements comprise a serpentine heater wire mounted to a foil sheet mounted on the outside surface of the liner sidewalls adjacent the bottom of the liner.

7. The refrigerator of claim 4 wherein the liner is a plastic liner and the evaporator is a serpentine evaporator mounted to the outside surface of the liner.

8. The refrigerator of claim 7 wherein the serpentine evaporator is mounted to the outside rear surface of the liner and the ambient heater comprises a pair of heater elements with one heater element attached to each of the liner sidewalls.

9. The refrigerator of claim 8 wherein the ambient heater elements comprise a serpentine heater wire mounted to a foil sheet mounted on the outside surface of the liner sidewalls adjacent the bottom of the liner.

10. A refrigerator adapted for use in a garage or outdoors where it can be subject to low ambient temperature conditions comprising:

a cabinet having a top wall, a pair of sidewalls, a rear wall and a bottom wall defining a front opening;

a plastic liner positioned inside the cabinet having a top wall, a pair of sidewalls, a rear wall and a bottom wall defining a refrigerated space and an outside surface;

foamed in place insulation between the outside surface of the liner and the inside surface of the cabinet;

a hinged insulated door mounted to close the front opening of the cabinet in a closed position and to permit access to the inside of the refrigerator in an open position;

a cooling system for cooling the inside of the refrigerator including a cooling thermostat for sensing the temperature in the refrigerated space to energize the cooling system when the temperature in the refrigerated space rises above a selected refrigerated space temperature;

an ambient heater for heating the refrigerated space comprising a first heater element mounted on one liner sidewall and a second heater element mounted on the other liner sidewall;

an ambient thermostat connected in an electrical circuit with the ambient heater and positioned to sense the air temperature outside the refrigerator, wherein the ambient thermostat is connected to energize the ambient heater when the temperature outside the refrigerator is below a first predetermined temperature; and

further including a heater thermostat positioned inside the refrigerator and connected in a circuit with the ambient thermostat and the ambient heater, and wherein the ambient thermostat is arranged to connect the ambient heater and heater thermostat to a power supply when the temperature outside the refrigerator falls below a first predetermined temperature, and connects the cooling thermostat to the power supply when the temperature outside the refrigerator rises above a second predetermined temperature, whereby the ambient heater is energized through the heater thermostat when temperatures outside the refrigerator fall to the first predetermined temperature and the cooling system is energized through the cooling thermostat when temperatures outside the refrigerator rise above the second predetermined temperature.

11. The refrigerator of claim 10 wherein the heater thermostat opens to de-energize the ambient heater when temperatures inside the refrigerator rise above a predetermined refrigerated space temperature.

12. The refrigerator of claim 10 wherein the ambient heater elements comprise a serpentine heater wire mounted to a foil sheet mounted on the outside surface of the liner sidewalls adjacent the bottom of the liner.

13. The refrigerator of claim 10 wherein the cooling system includes a compressor, an evaporator and a condenser connected in a cooling circuit, and wherein the compressor is provided with a crankcase heater connected in circuit with the ambient hearer for operation with the ambient heater, and the ambient thermostat is a bi-metal thermostat and is mounted to a discharge tube leading from the compressor to the condenser.

14. A refrigerator adapted for use in a garage or outdoors where it can be subject to low ambient temperature conditions comprising:

a cabinet having a top wall, a pair of sidewalls, a rear wall and a bottom wall defining a front opening and a machinery compartment;

a plastic liner positioned inside the cabinet having a top wall, a pair of sidewalls, a rear wall and a bottom wall defining a refrigerated space and an outside surface;

foamed in place insulation between the outside surface of the liner and the inside surface of the cabinet;

a hinged insulated door mounted to close the front opening of the cabinet in a closed position and to permit access to the inside of the refrigerator in an open position;

a cooling system for cooling the inside of the refrigerator including a compressor, an evaporator, and a condenser connected in a cooling circuit;

an adjustable cooling thermostat for sensing the temperature in the refrigerated space to energize the compressor for cooling the refrigerated space when the temperature inside the refrigerator rises above a selected refrigerated space temperature;

an ambient heater for hearing the refrigerated space comprising a first heater element mounted on one liner sidewall and a second heater element mounted on the other liner sidewall;

a heater thermostat for sensing the temperature in the refrigerated space and connected in circuit with the ambient heater to de-energize the ambient heater when the temperature in the refrigerated space rises above a predetermined refrigerated space temperature;

an ambient thermostat positioned to sense the air temperature outside the refrigerator and connected to the cooling thermostat and the heater thermostat wherein the ambient thermostat energizes the ambient heater through the heater thermostat when the temperature outside the refrigerator falls below a first predetermined temperature, and wherein the ambient thermostat energizes the cooling thermostat when the temperature outside the refrigerator rises above a second predetermined temperature.

15. The refrigerator of claim 14 wherein the ambient thermostat is a 3-way bi-metal thermostat located in the machinery compartment, and wherein the ambient thermostat operates to energize the ambient heater when the ambient temperature falls to approximately 32°

F., and operates to de-energize the ambient heater and energize the cooling thermostat when the ambient temperature rises to approximately 48°

F.

16. The refrigerator of claim 14 wherein the ambient heater elements comprise a serpentine heater wire mounted to a foil sheet mounted on the outside surface of the liner sidewalls adjacent the bottom of the liner.

17. The refrigerator of claim 14 wherein the evaporator is a serpentine evaporator mounted to the outside rear surface of the liner, the condenser is a static condenser mounted on the rear wall of the cabinet, and the top wall and bottom wall of the cabinet extend beyond the rear wall of the cabinet, and the top wall has a vent formed in the portion of the top wall extending beyond the rear wall for facilitating air flow over the static condenser.

18. The refrigerator of claim 14 wherein the hinged insulated door further includes a beverage container rack mounted on the inside of the door.